I understand the API usage basically does not cost us as follows based on Terms of Use.

6. Fees and Payments TMDb is committed to free and open access to our APIs for commercial and non-commercial purposes. However, providing the APIs does have real costs for TMDb. For uses of TMDb APIs over a certain rate or for certain types of commercial applications, TMDb reserves the right to charge fees for future use of or access to the TMDb APIs.

Basically, we would like to download all the databases (by accessing your APIs) to be cached on our side first then regularly access the APIs to be up-to-date.
Does downloading all databases violate your Terms of Use so to be considered as 'a certain API rate'? Or, do you actually prefer the way we are planning (your movie database caching plan)?

It would be perfect if you eventually could provide a pricing model for commercial use with a certain API rate to be clear.